A typical transmission oil sump is configured as a stamped steel pan bolted to the transmission case with a separate gasket between the pan and transmission case. Typically, a separate filter element is situated in the sump and connected to the inlet of a suction pump to filter oil as the oil is drawn from the sump and recirculated back through the transmission. By having separate components, the current arrangement requires assembly steps at the transmission factory, which separate assembly steps provide an opportunity for assembly errors, increased labor costs, and expense. In addition, stamped steel pans in and of themselves are relatively expensive. Moreover, the steel is expensive to recycle. An additional consideration is weight savings because by saving weight, fuel consumption and the resulting pollution is reduced. Over the years, enormous weight savings are accomplished by the cumulative effect of reducing weight in numerous small components wherein the weight reduction is sometimes in the form of ounces rather than pounds.
An approach is to make transmission oil sumps from plastic. Again, weight considerations are important. Accordingly, where components would not be robust because they are shielded from impacts by other components, they may be of lightweight construction. If components are of lightweight construction, then there need to be associated structures, also lightweight, which negate any problems which may occur due to lightweight construction. Therefore, savings in weight also may make desirable structural configurations which permit weight savings.